液相色谱-串联质谱法检测对虾中T-2毒素的 不确定度评定

Uncertainty evaluation of T-2 toxin determination in prawns by liquid chromatography-tandem mass spectrometry

中文关键词:  T-2毒素  液相色谱质谱联用法  对虾  不确定度

英文关键词:T-2 toxin  liquid chromatography-tandem mass spectrometry  prawn  uncertainty

中文摘要:

      目的 评定液相色谱-串联质谱检测对虾中T-2毒素的不确定度。方法 样品经乙酸乙酯提取, 无水硫酸钠脱水, 提取上清液氮气吹干后用1 mL 0.1%甲酸的甲醇:水溶液(3:7, V:V)定容, 正己烷除脂。基质匹配法定量。液相采用甲醇和0.1%甲酸酸化的5 mmol/L乙酸铵溶液梯度洗脱, 质谱采用电喷雾离子化方式下正离子的选择离子监测模式对T-2毒素的定量离子和定性离子进行监测。通过分析并计算检测过程中各不确定度分量得到合成标准不确定度。结果 本方法检测T-2毒素的合成标准不确定度为0.739 μg/kg, 取置信概率95%的扩展不确定度为1.5 μg/kg。所以, 试样中T-2毒素的测量结果为: X=(12.7±1.5) μg/kg, k=2。结论 此检测方法使外标法的定量结果更为真实有效, 方法不确定度的评定亦可为采用空白基质匹配法的现行相关检测方法的不确定度评估提供参考。

英文摘要:

      Objective To evaluate the uncertainty of T-2 toxin determination in prawns by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methods Samples were extracted by ethyl acetate, dehydrated by sodium sulfate, concentrated upper layer by nitrogen, dissolved by 1 mL 0.1% formic acid in methyl alcohol:water (3:7, V:V), and degreased by hexane. The target compounds were quantified by matrix-matched calibration standard. The T-2 toxin was separated on a reversed phase using a gradient elution program of 0.1% formic acid methyl alcoholsolution and 0.1% formic acid in 5 mmol/L ammonium acetate. LC–MS/MS with selected reactions monitoring (SRM) was used, and the T-2 toxin was identified based upon the intensities of fragments. Then the combined standard uncertainty was determined by analyzing and calculating various measurements of uncertainties. Results The relative combined standard uncertainty of this method was 0.739 μg/kg. The expanded uncertainty was 1.5 μg/kg when the fiducial probability was about 95%. So the measurement result of T-2 toxin in the sample was (12.7±1.5) μg/kg, k=2. Conclusion This detection method makes the results of external standard method more realistic and effective. The evaluation method of measurement uncertainty in this article can also provide a reference for the correlation detection method which quantified by matrix-matched calibration standard.